Ryanair is prepared to sell its stake in Aer Lingus to another European airline as part of an ongoing probe by the Competition Commission into the shareholding.

The Irish budget carrier denies its 29% stake means it has influence over its rival’s commercial strategy or that it lessens competition.

But in a surprise move today, Ryanair issued an undertaking to the UK competition authority that it will “undertake to unconditionally” sell its shareholding to any other EU airline that makes an offer for Aer Lingus.

“This remedy unconditionally removes any ability by Ryanair to block any future takeover of Aer Lingus by another EU airline,” a spokesman said.

Ryanair has held the stake for more than six years and has itself made several failed takeover bids for the former Irish flag carrier.

The spokesman said: “It is clear from the CC’s own provisional findings report that it has found no evidence of any lessening of competition between Ryanair and Aer Lingus.

“In fact, Ryanair’s recent (third) offer for Aer Lingus was prohibited by the EU precisely because of the evidence, submitted by both Aer Lingus and the Irish government, that competition between Ryanair and Aer Lingus has “intensified” during the past six and a half years.

“These inconvenient facts have reduced the CC’s Simon Polito (chairman) and Roger Davis (Member) to inventing new and fantastical “concerns” in order to justify their apparently premeditated and biased “thinking” that Ryanair should be forced to sell down this six and a half year old minority stake.

“The only remaining ‘concern’ they can now dream up is that Ryanair’s 29% stake ‘might’ prevent another EU airline buying Aer Lingus; despite six and a half years of evidence (and repeated public statements) that no other EU airline has any interest in acquiring Aer Lingus.

“In order to remove any remaining shred of credibility from this CC process and eliminate any doubt about this imaginary albeit non-existent ‘concern’, Ryanair has now agreed that it will unconditionally sell its six and a half year old minority stake to any other EU airline which makes an offer for, and acquires more than 50.1% of, Aer Lingus shares, at the same price and terms which are accepted by these other 50.1% of Aer Lingus shareholders.

“This bogus CC ‘concern’ has now been fatally undermined thereby removing any requirement for a divestment of Ryanair’s six and a half year old minority shareholding which even the CC now admits hasn’t given Ryanair any influence, and Aer Lingus admits has led to intensified competition to the benefit of the perhaps one or maybe two UK consumers who even fly Aer Lingus.”

The CC provisionally found in May that, against a background of consolidation in the airline industry, Ryanair’s shareholding obstructs Aer Lingus’s ability to merge or combine with another airline to build scale and achieve synergies to remain competitive.

It said that Ryanair faces having to reduce its shareholding because ts shareholding could reduce competition on routes between the UK and Ireland.